Experiments have shown that when 3H-uridine is injected into the eye of fish during regeneration of the optic nerves, large amounts of 3H RNA can be detected within optic axons and axonal growth cones as regenerating fibers re-enter the optic tectum, (Gambetti, et al., 1978). Biochemical evidence has shown that a large fraction of this 3H-RNA is 4S RNA (Ingoglia and Tuliszewski, 1976). It has been suggested that 4S RNA is synthesized in retinal ganglion cells and is then axonally transported into the growing fibers. This study investigates some of the characteristics of axonal 4S RNA in regenerating optic nerves of goldfish. Two of the proposed experiments attempt to determine whether 4S RNA is transported throughout regeneration, or only at a specific stage (or stages) of nerve growth. These experiments utilize radioactive tracer techniques, and biochemical extraction of RNA. Polyacrylamide gel electrophoresis is used to identify RNA species. Other experiments attempt to determine whether RNA, once transported to the tectum remains in optic axons or if axonal RNA is transferred to surrounding tectal cells. These experiments also utilize biochemical techniques, coupled with EM autoradiography of goldfish tecta. Other experiments will determine if axonally transported 4S RNA is transfer RNA. These experiments employ surgical and biochemical techniques, followed by determination of radioactivity using liquid scintillation counting. Finally, some experiments examine the association of spermidine with axonally transported RNA. It is suggested that axonally transported spermidine may serve as a stabilizer of RNA structure or as a ribonuclease inhibitor, thus preventing the degradation of RNA during its axonal migration. These experiments utilize radioactive tracers, polyacrylamide gel electrophoresis, and amino acid analysis, to identify axonally transported spermidine. These experiments study the nature of axonal RNA in regenerating optic nerves of goldfish, and will allow us to better understand the functional role of RNA in regenerating nerves.